P1 or F1 which best to use for pollinator

[cruzin]

Im going to pollinate a female for regular seeds. I have both pollen from the P1 (parent) male and I have pollen from F1 (brother). Can someone tell me there understanding of which pollen would be the best to use to lock in the goodness of the strain which is Master Kush regular seeded plant. thanks.

 

[threatco]

I am curious on this my self.

 

[chemistry]

Do both, you cant go wrong then, and don't forget to post your results on here, with pictures.